Fix source maps for template literals (#16515)

* Add test

* Fix source maps for template literals

packages/babel-core/test/fixtures/transformation/source-maps/template-literal/input.js

@@ -0,0 +1 @@
+let a = `a${b}c`;

packages/babel-core/test/fixtures/transformation/source-maps/template-literal/options.json

@@ -0,0 +1,3 @@
+{
+  "sourceMaps": true
+}

packages/babel-core/test/fixtures/transformation/source-maps/template-literal/output.js

@@ -0,0 +1 @@
+let a = `a${b}c`;

packages/babel-core/test/fixtures/transformation/source-maps/template-literal/source-map-visual.txt

@@ -0,0 +1,20 @@
+  (1:0-4) let a =                 <--    (1:0-4) let a = 
+          ^^^^                                   ^^^^
+
+  (1:4-5) let a = `               <--    (1:4-5) let a = `
+              ^                                      ^
+
+  (1:5-8) et a = `a${             <--    (1:5-8) et a = `a${
+              ^^^                                    ^^^
+
+ (1:8-12) a = `a${b}c`            <--   (1:8-12) a = `a${b}c`
+              ^^^^                                   ^^^^
+
+(1:12-13) `a${b}c`;               <--  (1:12-13) `a${b}c`;
+              ^                                      ^
+
+(1:13-16) a${b}c`;                <--  (1:13-16) a${b}c`;
+              ^^^                                    ^^^
+
+(1:16-17) b}c`;                   <--  (1:16-17) b}c`;
+              ^                                      ^

packages/babel-core/test/fixtures/transformation/source-maps/template-literal/source-map.json

@@ -0,0 +1,15 @@
+{
+  "version": 3,
+  "names": [
+    "a",
+    "b"
+  ],
+  "sources": [
+    "source-maps/template-literal/input.js"
+  ],
+  "sourcesContent": [
+    "let a = `a${b}c`;"
+  ],
+  "mappings": "AAAA,IAAIA,CAAC,GAAG,IAAIC,CAAC,GAAG",
+  "ignoreList": []
+}

packages/babel-generator/src/generators/template-literals.ts

@@ -10,27 +10,24 @@ export function TaggedTemplateExpression(
   this.print(node.quasi, node);
 }
 
-export function TemplateElement(
-  this: Printer,
-  node: t.TemplateElement,
-  parent: t.TemplateLiteral,
-) {
-  const isFirst = parent.quasis[0] === node;
-  const isLast = parent.quasis[parent.quasis.length - 1] === node;
-
-  const value = (isFirst ? "`" : "}") + node.value.raw + (isLast ? "`" : "${");
-
-  this.token(value, true);
+export function TemplateElement(this: Printer) {
+  throw new Error("TemplateElement printing is handled in TemplateLiteral");
 }
 
 export function TemplateLiteral(this: Printer, node: t.TemplateLiteral) {
   const quasis = node.quasis;
 
+  let partRaw = "`";
+
   for (let i = 0; i < quasis.length; i++) {
-    this.print(quasis[i], node);
+    partRaw += quasis[i].value.raw;
 
     if (i + 1 < quasis.length) {
+      this.token(partRaw + "${", true);
       this.print(node.expressions[i], node);
+      partRaw = "}";
     }
   }
+
+  this.token(partRaw + "`", true);
 }

packages/babel-generator/test/fixtures/sourcemaps/template-literal-newline/source-map.json

@@ -7,6 +7,6 @@
   "sourcesContent": [
     "// Newline\n`before\nafter`;\n\n// Newline newline\n`before\n\nafter`;\n\n// Newline LineContinuation\n`before\n\\\nafter`;\n\n// LineContinuation\n`before\\\nafter`;\n\n// LineContinuation newline\n`before\\\n\nafter`;\n\n// LineContinuation LineContinuation\n`before\\\n\\\nafter`;"
   ],
-  "mappings": "AAAA;AACC;AACD,MAAM;;AAEN;AACC;AACD;AACA,MAAM;;AAEN;AACC;AACD;AACA,MAAM;;AAEN;AACC;AACD,MAAM;;AAEN;AACC;AACD;AACA,MAAM;;AAEN;AACC;AACD;AACA,MAAM",
+  "mappings": "AAAA;AACA;AACA,MAAM;;AAEN;AACA;AACA;AACA,MAAM;;AAEN;AACA;AACA;AACA,MAAM;;AAEN;AACA;AACA,MAAM;;AAEN;AACA;AACA;AACA,MAAM;;AAEN;AACA;AACA;AACA,MAAM",
   "ignoreList": []
 }

packages/babel-plugin-transform-modules-commonjs/test/fixtures/strict/import/source-map-visual.txt

@@ -79,11 +79,8 @@
  (10:0-4) foo3``;                 <--   (9:4-13) (0, _foo.foo3)``;
           ^^^^                                       ^^^^^^^^^
 
- (10:4-5) foo3``;                 <--  (9:13-14) foo3)``;
-              ^                                      ^
-
- (10:5-6) oo3``;                  <--  (9:14-16) oo3)``;
-              ^                                      ^^
+ (10:4-6) foo3``;                 <--  (9:13-16) foo3)``;
+              ^^                                     ^^^
 
  (10:6-7) o3``;                   <--  (9:16-17) 3)``;
               ^                                      ^

packages/babel-plugin-transform-modules-commonjs/test/fixtures/strict/import/source-map.json

@@ -16,6 +16,6 @@
   "sourcesContent": [
     "import foo from \"foo\";\nimport { default as foo2 } from \"foo\";\nimport { foo3 } from \"foo\";\nimport * as foo4 from \"foo\";\n\nfoo;\nfoo2;\nfoo3;\nfoo3();\nfoo3``;\nfoo3?.();"
   ],
-  "mappings": ";;AAAA,IAAAA,IAAA,GAAAC,YAAA,CAAAC,sBAAA,CAAAC,OAAA;AAAsB,IAAAC,IAAA,GAAAJ,IAAA;AAKtBK,YAAG;AACHC,YAAI;AACJC,SAAI;AACJ,IAAAA,SAAI,EAAC,CAAC;AACN,IAAAA,SAAI,CAAC,EAAC;AACN,IAAAA,SAAI,IAAG,CAAC",
+  "mappings": ";;AAAA,IAAAA,IAAA,GAAAC,YAAA,CAAAC,sBAAA,CAAAC,OAAA;AAAsB,IAAAC,IAAA,GAAAJ,IAAA;AAKtBK,YAAG;AACHC,YAAI;AACJC,SAAI;AACJ,IAAAA,SAAI,EAAC,CAAC;AACN,IAAAA,SAAI,GAAE;AACN,IAAAA,SAAI,IAAG,CAAC",
   "ignoreList": []
 }